Sewage system

ABSTRACT

A SELF-CONTAINED, RECIRCUALTING TOILET INCLUDES A MAIN HOLDING TANK HAVING A DRAIN OPENING IN THE BOTTOM THEREOF AND AN ACCESS OPENING IN THE TOP OF THE TANK IN SUBSTANTIALLY VERTICALLY SPACED RELATION TO THE DRAIN OPENING. A UNITARY PUMP, FILTER, AND DRAIN VALVE ASSEMBLY IS INSERTED THROUGH THE ACCESS OPENING WITH SAID DRAIN VALVE SEALING THE DRAIN OPENING WHEN THE ASSEMBLY IS LOCKED IN PLACE. THE DRAIN VALVE SEAL FORMS PART OF THE FILTER AND INCLUDES AN OUTWARDLY EXTENDING LIP WHICH ENGAGES THE SURFACE OF THE TANK TO FOEM ONE SEAL, AND A CIRCUMFERENTIALLY EXTENDING RIDGE AXIALLY SPACED FROM THE RIDGE WHICH ENGAGES THE INSIDES OF THE DRAIN OPENING TO FORM A SECOND SEAL.

Nov. 2, 1911 R. C. HELKE Em -:16,4s5

SEWAGE SYSTEM IO'/ ATTORNEYS Nov. 2, 1971 R'C- HEI-KE Erm' v 3,616,465

' sEwAGE SYSTEM Original Fled Deo. 9. 1968 2. Sheets-Sheet n FIG-3 rPatented Nov. 2, 1971 3,616,465 SEWAGE SYSTEM Robert C. Helke, Dayton,Charles E. Van Gilder, Kettering, and Merlin S. Miller, Bradford, Ollio,assignors to Koehler-Dayton, Inc., Dayton, Ohio Original applicationDec. 9, 1968, Ser. No. 782,240, now Patent No. 3,545,011, dated Dec. 8,1970. Divided 4and this application June 4, 1970, Ser. No. 43,445 Int.Cl. E03d 1/00 U.S. Cl. 4-1 5 Claims ABSTRACT OF THE DISCLOSURE Aself-contained, recirculating toilet includes a main holding tank havinga drain opening in the bottom thereof and an access opening in the topof the tank in substantially vertically spaced relation to the drainopening. A unitary pump, filter, and drain valve assembly is insertedthrough the access opening lwith said drain valve sealing the drainopening when the assembly is locked in place. The drain valve seal formspart of the filter and includes an outwardly extending lip which engagesthe Surface of the tank to form one seal, and a circumferentiallyextending ridge axially spaced from the ridge which engages the insideof the drain opening to form a second seal.

RELATED APPLICATIONS This is a division of application Ser. No. 782,240,filed Dec. 9, 1968, now Pat. No. 3,545,011. Reference is also made tocopending application Ser. No. 782,062 filed Dec. 9, 1968, entitledFlushing Manifold for Portable Toilet, assigned to the same assignee asthe present invention.

BACKGROUND OF THE INVENTION A need has long existed for portable toiletsof sufficiently small size and low cost for use in light aircraft,trailers, boats, or in any other environment where a self-containedrecirculating toilet system is desired or required by law. Severalportable toilet systems have been developed, each including a mainholding tank, a toilet bowl which empties into the holding tank, aflushing manifold which surrounds the bowl, a filter, and a pump to drawliquid through the filter from the holding tank and force it into theflushing manifold. Each of these components in prior art toilets aremounted in separate means, which increases the cost of construction andrequires considerable time to disassemble for cleaning and replacement.

SUMMARY OF THE INVENTION This invention relates to an improvedself-contained recirculating portable toilet wherein the pump, filterand drain valve seal are ymounted together as a unitary assembly whichmay be easily removed when cleaning the toilet. The invention alsorelates to an improved drain valve seal which is mounted at thelowermost portion of the filter and which engages the drain opening inthe main holding tank when the uppermost portion of,the assembly restsagainst the top surface of the main holding tank.

By so constructing the main holding tank that with the access openinglocated substantially vertically above the drain opening, a singlemolded member may be used to support a filter, a drain valve, and a pumpwhich may be included within the lter. By dimensioning this unit so thatfastening means at its uppermost portion engage the top of the mainholding tank when the seal at the bottom of the filter is inserted intothe drain opening, the

drain valve seal may be closed positively merely by securing thefastening means.

It is therefore an object of this invention to provide an improvedself-contained, recirculating portable toilet wherein the pump, filter,and drain valve seal are formed on a single member for easy removal forcleaning and lower cost; to provide an improved drain valve having apair of seals to insure that the drain opening is sealed completely whenthe pump and filter are secured in their operating position, one sealengaging the surface around the drain opening and the other sealengaging the inside surface of the drain opening; and to provide a drainvalve which not only seals the drain opening but also functions as anend portion of the filter.

Other objects and advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is a plan view of the improvedself-contained toilet showing the location of the pump motor and thetoilet bowl, and also showing in cross section a portion of the flushingmanifold which surrounds the toilet bowl;

FIG. 2 is an elevational view of the left side of the toilet shown inFIG. l with a check valve and a portion of the inlet hose carrying thecleaning water shown in cross section;

FIG. 3 is a cross sectional view of the pump, filter, and seal for thedrain opening;

FIG. 4 is an enlarged cross sectional view of the improved seal showingits configuration prior to its being inserted into the drain opening;

FIG. 5 is an enlarged cross sectional view showing the configuration ofthe seal after it has been inserted into the drain opening with itsdownwardly curved circumferentially extending lip engaging the surfaceof the tank around the drain opening; and

FIG. 6 is an enlarged cross sectional view showing the configuration ofthe seal after it has been fully inserted in the drain opening andrelative movement has occurred between the seal and the filter.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2,the self-contained recirculating toilet of this invention includes amain holding tank 10 which is preferably molded from fiberglass orplastic, having a lower portion 11 in which a drain opening 12 isformed. Hand holds 13 and 14 are formed in the sides of the tank tofacilitate handling of the toilet during removal from its operatingposition. Not shown is the toilet seat and the frame under which thetoilet is positioned when in use.

A top 15 for the main holding tank 10, also formed from a single pieceof molded fiberglass, is mated and sealed to the ymain holding tank andhas formed therein a toilet bowl 16. A generally horizontal surface 17surrounds the top of the bowl 16, and an inverted U-shaped member 18 isspaced vertically from this surface to form therewith a flushingmanifold 20. The surface 17 is horizontal in the embodiment shown butmay also be sloped toward the bowl 16 in order to facilitate drainingthe flushing liquid from the manifold. The outer downwardly extendingportion of the member 18 engages the outer surface of the bowl 16 inwatertight relation. Preferably, the fiberglass 15 is so molded thatwhen the member 18 is mounted in place, a smooth outer surfaceappearance is created.

The inner downwardly extending portion of the U- shaped member 18 isspaced radially infwardl'y from the bowl and extends slightly below thetop of the surface 17 to form an open slot 21 which extends continuouslyaround the entire periphery of the bowl. Flushing liquid flows into thebowl through an opening 22. As viewed in FIG. 1, flushing liquid willflow in a clockwise direction and diagonally downwardly across thesurface of the bowl 16 to provide the necessary cleaning action. A moredetailed explanation of the flushing manifold will be found in the abovementioned application Ser. No. 782,062.

An access opening 27 (FIG. 3) is provided in the upper horizontalsurface 28 of the fiberglass member 15, and this access opening 27 ispositioned substantially vertically above the drain opening 12. A member3()` is inserted through the access opening 27 and carries with it apump motor 31 and a filter 32. A drain seal 35, carried at the lowermostportion of the filter 32, fits into the drain opening 12 when the member30 is installed.

A flange 36 is formed at the top of the member 30 and carries with it aplurality of fastening means 37, such as the commonly used one-quarterturn fasteners. A gasket 38 between the fiange 36 and the upper surface28 insures that a watertight seal will exist between the member and theupper surface 28 of the main holding tank 10. The length of the member30 is such that when the flange 36 is locked in place, the seal 35 willalso be in its operation position. Guide pins 39 (FIGS. 1 and 2) aid inaligning the member 30 within the opening 27.

A pump 40 is contained within the member 30 and includes a shaft 41having an upper end connected to the drive shaft of motor 31 and a lowerend connected to an impeller 43. A cylindrical housing 44 surrounds theimpeller 43 and an outlet 4S located at its upper right, as shown inFIG. 3. Thus, filtered liquid will be drawn into the opening in thelower portion of the housing 44 by action of the impeller 43 and forcedout through the outlet 45. A hose 46 carries the liquid to a fitting 47,also formed in the flange 36 of the member 30. This constructionsimplifies the molding of the member 30, which is a single piece, asdescribed. Referring again to FIG. l, a hose 49 connects the fitting 47with the inlet 22 of the flushing manifold 20.

The filter 32 consists of a hollow cylindrical member 51 having aplurality of internal axially extending ribs 52. A plurality of slots 53are cut into the member 51, through which liquid may flow but which areclosely spaced to prevent entry of solid particles. The slots are cutclear through the cylindrical member 51 but are not cut through the ribs52 thus retaining the structural integrity of the filter.

The bottom of the cylindrical member 51 is sealed by exible resilientmember 35, preferably formed from silicon rubber or neoprene. Thisflexible member includes a plurality of flow straightening vanes 55which cooperate with the cylindrical pump housing 44 to direct filteredliquid into the pump 40.

Reference is now made to FIGS. 3 through 6 which show the relationshipbetween the fiexible seal 35, the filter 32, and the drain opening 12which is formed in the bottom of the tank 10. In FIG. 4, the cylindricalmember 51 of the filter 32 is shown as having an outwardly extending lipon which is formed a conically shaped cam surface 71. This outwardlyextending lip 70 cooperates with a conically shaped slot 72 in the seal35 to hold the seal 35 in place on the filter 32.

The body of the seal 35 has a shape in cross section in a plane parallelto the bottom of the tank 10 which generally corresponds to the shape ofand substantially fills the drain opening 12. Preferably, the drainopening is circular. The seal 35 includes an outwardly extending lip 75which is curved downwardly toward the bottom surface of the tank so thatwhen it engages this surface it will be held tightly against the surfaceby the resiliency of the material from which the seal 35 is made. Theseal 35 also includes an outwardly extending ridge 76 spaced axiallydownwardly from the lip 75. A cam surface 72 spaced radially inwardlyfrom the ridge cooperates with the cam surface 71 on the filter 32 sothat as the filter is moved downwardly relative to the seal, the sealwill expand. The diameter of the ridge 76 is such that, when in theposition shown in FIG. 4, it will fit freely into the opening 12.

FIG. 5 shows the seal after it has been inserted into the drain openingbut before relative movement occurs between the seal 35 and the filter32. The outwardly extending lip 75 engages the surface of the tankbottom around the edge of the opening 12, and since this lip is curveddownwardly, it forms a first seal. As the filter 32 is moved furtherdownwardly, the filter will move relative to the seal 35 since the sealis now restrained from further movement by the outwardly extending lip75. Therefore relative motion occurs between the seal 35 and filter 32which causes the cam surface 71 on the filter 32 to move relative to thecam surface 72 formed in the seal 35 thus causing the seal to expandforcing the circumferentially extending ridge 76 into sealing engagementwith the interior surface of the opening 12 to form a second seal asshown in FIG. 6. Thus, two sealing surfaces are created, the firstbetween the outwardly extending lip 75 and the bottom surface of thetank 10 which surrounds the opening 12, and the second between thecircumferentially extending ridge 76 and the inside surface of theopening 12. The. seal 35 and the filter 32 are held in the relativeposition shown in FIG. 6 by the fasteners 37 which are received intothreaded inserts installed in the top surface 28 of the tank 10.

The seal arrangement thus described allows the easy removal of the seal35 from the drain opening 12 since, as the filter 32 is moved upwardlyrelative to the seal, air is permitted to pass between thecircumferentially extending ridge 76 and the inside of the drain opening12 to relieve the vacuum formed in the space 78 between the ridge 76 andthe lip 75. Thus, the diameter of the ridge 76 must be carefullycontrolled, otherwise difliculty may be experienced in removing the sealonce it is forced in place.

Since the pump motor 31, the pump 40, the filter 32, and the drain seal35 are all mounted on the single molded member 30, easy cleaning of thisassembly is provided and a reduction in the cost of fabricating aportable toilet of this type is realized.

While the form of apparatus herein described constitutes a preferredembodiment of the invention, it is to be understood that the inventionis not limited to this precise form of apparatus, and that changes maybe made therein without departing from the scope of the invention whichis defined in the appended claims.

What is claimed is:

1. A seal for closing an opening formed in a surface comprising a bodyof resilient material having a shape in cross section in a planeparallel to the surface which generally corresponds to the shape of andsubstantially fills the opening in the surface;

an outwardly extending lip on said body adapted to engage the surfacearound the edge of the opening therein in Sealing relation;

a circumferentially extending ridge on said body axially spaced fromsaid lip and adapted to fit against the inside of the opening when saidlip engages the surface;

a cam surface in said body spaced radially inwardly from said ridge; and

means cooperating with said cam surface for forcing said ridge outwardlyinto sealing engagement with the inside of the opening as said meansmoves axially relative to said body after said lip engages the surfacein sealing relation.

2. A seal as defined in claim 1 wherein said body is formed fromneoprene.

3. A seal as dened inclaim lwherein said lip and said circumferentiallyextending ridge are formed integrally with said body.

4. A seal as delined in claim 1 wherein said lip is curved toward saidridge so that as said body is moved into the opening, said lip isattened and held against the surface by the resiliency of said materialto provide an improved seal.

S. A seal as defined in claim 1 `wherein said body is carried by saidforcing means into the opening and wherein said body is restrained fromfurther movement into the opening by said lip after it has flattenedagainst the surface thereby causing relative movement between said camsurface and said forcing means to expand said circumferentiallyextending ridge into sealing relation with the inside of the opening.

References Cited UNITED STATES PATENTS 3,473,171 10/1969 Palmer 4-782,573,552 10/1951 Detzel 138-96 UX SAMUEL ROTHBERG, Primary ExaminerU.S. Cl. X.R. 13S-96

